Amazon supports POST and PUT requests with its CloudFront CDN service.
The FAQ says that
Amazon CloudFront does not cache the responses to POST, PUT, DELETE, and PATCH requests – these requests are proxied back to the origin server. You may enable caching for the responses to OPTIONS requests.
I understand how a CDN improves performance in getting content from a server to a client. How does it improve performance in getting getting content from the client to a server? How can uploads be made faster by introducing a middleman?
In the context of uploading files, does having the CloudFront distribution backed by S3 make a difference? If so, how?